1. Priority
Priority is claimed to German Patent Application No. 102007050461.8, filed on Oct. 18, 2007. The aforementioned priority document is incorporated herein by reference in its entirety.
2. Field of the Invention
The field of the present invention relates to vehicle roofs, and in particular vehicle roofs including a folding slat arrangement which may be used to cover and uncover an opening in the roof.
3. Background
There are a number of types of sliding roofs for vehicles, for example rigid, one-piece, transparent and non-transparent sliding roofs. Slatted roofs made of transparent materials are also manufactured. These are described, inter alia, in DE 44 15 649 C1 and EP-A-591 644. EP-A-1 125 778 describes a vehicle roof which is capable of opening and has at least two roof systems which are arranged one behind the other and are capable of opening separately. A feature of these roofs consists in the fact that the combination of individual slats is broken up when it is opened. An additional, separable sealing face between the individual slats is therefore necessary. This requires complex kinematics (for example DE 19959542 A1) and high stiffness of the components of the individual slats in order to maintain the sealing force over the life span. The structure for absorbing the sealing forces reduces the transparent see-through area considerably (by about 50%) and requires a high installation space, a fact which can impair the freedom of design and, in particular, the aerodynamics. Furthermore, the slatted roofs described can be moved exclusively in the longitudinal axis of the vehicle since, on the one hand, the necessary installation space would be too great if they moved together along, for example, the transverse axis of the vehicle, and on the other hand, severe wind noise can occur because of the slats (or components) which protrude from the contour of the vehicle. Window blinds made of glass, which are connected in a material-bonded manner, are also known (DE 29607921). Glass slats of this kind have very high stiffness with, at the same time, high weight and low impact strength.
If glass is used because of its high stiffness (modulus of elasticity about 70000 MPa), its high density is a major disadvantage. Plastics, for example polycarbonates, have a considerably lower density than glass and are, at the same time, just as transparent. However, they have far lower stiffness (modulus of elasticity about 2400 MPa). It is possible these days, by means of complex geometries and, in some cases, complex stiffening elements, to manufacture panoramic roofs which are likewise made of polycarbonate.